Organic Maize Growth and Mycorrhizal Root Colonization Response to Tillage and Organic Fertilization

The influence of conventional and no-tillage on mycorrhizal root colonization, soil properties and yield, was studied for 2 years in an experimental field of organic maize, fertilized by cattle manure or by seaweed compost. The no-tillage system improved soil macroporosity, increased organic carbon content, and enhanced the mean weight diameter of soil aggregates. Similarly, it had a positive effect on plant growth. Root density, leaf area index, biomass, grain yield and mycorrhizal root colonization were significantly affected by tillage system. Fertilization with manure and compost improved soil structure and aeration, thus favoring a higher mycorrhizal colonization of organic maize. The improved soil physical properties were positively related to mycorrhizal root colonization. High correlation coefficients of determination (r2) were also found between mycorrhizal root colonization and plant characteristics. It is concluded that the no-tillage system can improve the productivity of organic agriculture via pronounced arbuscular mycorrhizal root colonization.